Synergistic inhibition of the PI3K-AKT-mTOR signaling pathway in idiopathic pulmonary fibrosis by Sanleng-Ezhu: a multi-omics and experimental study.

Idiopathic pulmonary fibrosis (IPF), the most prevalent form of interstitial lung disease, currently lacks effective therapeutic interventions that confer survival benefits. Sanleng (SL) and Ezhu (EZ), a classic traditional Chinese medicine herb-pair widely used in clinical practice for pulmonary fibrosis, have shown potential in treating IPF, yet their synergistic effects and underlying mechanisms remain elusive. The study aims to elucidate the synergistic therapeutic effects and molecular mechanisms behind. Integrated single-cell RNA sequencing (scRNA-seq) analysis identified IPF-associated epithelial (IPF-Epi) cells as key contributors to disease pathogenesis, with significant enrichment in the PI3K-Akt signaling pathway. Bulk RNA sequencing combined with network pharmacology approaches further revealed 13 potential therapeutic targets of SL-EZ, with the PI3K-Akt pathway ranked as the top enriched signaling cascade. In vivo validation using a bleomycin-induced murine model of IPF demonstrated that the SL-EZ herb-pair markedly improved lung histopathological architecture, attenuated inflammatory infiltration, and alleviated fibrotic remodeling. Mechanistically, the therapeutic efficacy was associated with the suppression of the hyperactivated PI3K-AKT-mTOR signaling pathway. Notably, combination therapy with SL-EZ exerted superior protective effects compared to either monotherapy, highlighting a synergistic interaction between the two herbs. Collectively, these findings indicate that SL-EZ targets IPF-relevant epithelial cells and ameliorates both inflammatory and fibrotic processes, primarily through modulation of the PI3K-AKT-mTOR axis, thereby providing novel mechanistic insights into the therapeutic potential of this traditional herb-pair for IPF.